Method for making an electrotherapeutic sole

ABSTRACT

A method for making an electrotherapeutic sole, where the electrotherapeutic sole includes of nitrile-butadiene rubber (38%˜42% by weight), conductive carbon black (37%˜42% by weight), a softening oil (14%˜17% by weight), a processing aid (3%˜5% by weight), and an accelerant (1%˜2% by weight) and has a top portion protrudingly provided with a plurality of electrode protuberances that correspond in positions to the acupoints in a human sole; the electrotherapeutic sole is also provided with a socket, thereby an electrotherapeutic pulse output terminal inserted into the socket can send the electrotherapeutic pulses generated by an electrotherapeutic pulse generator sequentially through the socket and the conductive carbon black in the electrotherapeutic sole to the tips of the electrode protuberances to massage the corresponding acupoints in the human sole.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional application of pending U.S. patentapplication Ser. No. 15/590,041, filed May 9, 2017, of which the entiredisclosure of the pending, prior application is hereby incorporated byreference.

FIELD OF THE INVENTION

The present invention relates to an electrotherapeutic sole and a methodfor making the same. More particularly, the invention relates to anelectrotherapeutic sole that is configured to connect with anelectrotherapeutic pulse generator (e.g., a TENS/EMS device) and thatdoes not require a complicated internal circuit in order to send theelectrotherapeutic pulses generated by the electrotherapeutic pulsegenerator to the acupoints in the sole of a human foot.

BACKGROUND OF THE INVENTION

Acupoints, which constitute an important part of the Chinese meridiantheories, refer to specific positions on the superficial meridians(i.e., pathways distributed in the human body to facilitate thecirculation of life force, or qi, between body organs) that serve asconfluences, relay stations, and entrances/exits of qi. When a personfalls ill, the corresponding acupoints tend to have such pathologicalreactions as pain (when pressed), soreness, numbness, nodule formation,and/or swelling. A doctor, therefore, can diagnose a patient's diseaseaccording to the pathological reaction(s) taking place and may alsotreat the patient by stimulating the corresponding acupoints.

Conventionally, acupoints are stimulated by acupuncture or tui na. Withthe advancement of science and medicine, however, electrotherapy hasbeen a major means of acupoint stimulation, given the fact thatacupoints have proved to have low electrical resistance and highconductivity. For example, Dr. Richard Croon of Germany found arelationship between acupoints and the low-resistance points on theskin; Dr. Reinhold Voll, also of Germany, verified the existence ofseveral low-resistance superficial channels in the human body thatresemble the meridians in traditional Chinese medicine; and Dr. YoshioNakatani of Japan found a relationship between acupoints and ryodoraku,a specific form of acupuncture developed by the Japanese. Electrotherapyis a physical treatment involving electrical stimulation and isconducted as follows. To start with, electrode pads are attached to apatient's skin. Then, a series of current signals generated by anelectrotherapeutic signal generator are sent through the electrode padsto the muscle groups under the skin to induce rhythmic yet involuntarypartial contraction and relaxation of the muscle groups, thusstimulating the intended acupoints in a way similar to acupuncture.

Electrotherapy is non-invasive, non-pharmacological, and hence an idealtreatment for personal health maintenance at home. Transcutaneouselectrical nerve stimulation (TENS) and electrical muscle stimulation(EMS), for instance, are two common methods of electrotherapy nowadays.TENS, which uses low-frequency pulse current to control pain, is basedon the “gate control theory”, according to which epidermal nerves (e.g.,the Aβ nerve fibers) can be stimulated with weak low-frequency currentto generate signals that turn off the “gate” of the correspondingsensory nerves (e.g., the Aδ nerve fibers and the C nerve fibers),thereby stopping the conduction of pain and producing a painkillingeffect. EMS, on the other hand, causes muscle contraction and relaxationby stimulating the corresponding motor nerves so that passive physicalexercise is carried out for the intended treatment or training. Byadjusting the current frequency of the electrotherapeutic signalsgenerated by a TENS or EMS device, therefore, simulated acupuncture canbe achieved to stimulate the target acupoints.

However, the inventor of the present invention has found that most ofthe aforesaid electrotherapeutic instruments use electrode pads as theelements required for transmitting electrotherapeutic signals, and thateach time electrotherapy is performed, each target acupoint has to beattached with one electrode pad because the electrode pads generallyhave a small surface area and must be adhesively and securely attachedto all the intended acupoints respectively in order to produce theexpected electrotherapeutic effect. Accordingly, multiple electrode padsare needed when it is desired to conduct electrotherapy on severalacupoints at the same time, and the electrode pads must be respectivelyand adhesively attached to the acupoints before the electrotherapybegins so that all the acupoints can receive the therapy at once. Itwould be very inconvenient if electrotherapy is applied to a pluralityof acupoints by turns. The sole of a human foot, for example, has manyacupoints and includes reflex areas for almost all the organs in thebody. It is common practice, therefore, to manually massage theacupoints in the soles, with a view to stimulating the reflex areas,promoting blood circulation through the body organs, discharging thewastes or toxins in the organs, and thereby enhancing metabolism. But ifit is desired to stimulate the acupoints in the soles by electrotherapyinstead of manual massage, the electrode pads cause problems. Since eachelectrode pad covers only a small area, and different parts of a humansole vary greatly in curvature, a large number of electrode pads must beused; nevertheless, it is difficult to firmly attach the electrode padsto all the intended acupoints respectively.

As a solution, shoe soles adapted for electrotherapy were developed,allowing a user's entire foot to stamp on such a sole. These soles aretypically provided therein with additional electronic elements (e.g.,conductive wires) or are coated with a conductive material such that themanufacturing process is exceedingly complicated. Moreover, when stampedon repeatedly for a long time, the electronic elements are prone todamage (e.g., the conductive wires may be broken), or the conductivematerial may peel off. In either case, the sole in question will loseits electrotherapeutic effect. Hence, the issue to be addressed by thepresent invention is to design a novel sole structure that not only hasa simple production process, but also is structurally simple to ensure alasting electrotherapeutic effect during long-term use.

BRIEF SUMMARY OF THE INVENTION

In light of the aforementioned drawbacks of the conventionalelectrotherapeutic soles, the inventor of the present inventionincorporated years of practical experience in the industry intoextensive research and repeated tests and finally succeeded indeveloping the electrotherapeutic sole disclosed herein and a method formaking the same. The present invention is intended to provide a betterelectrotherapeutic sole that will be favored by the general public.

It is an objective of the present invention to provide anelectrotherapeutic sole that includes a main body, a plurality ofelectrode protuberances, and a socket. The main body is a thin platecomposed at least of nitrile-butadiene rubber (NBR) at a weightpercentage of 38%˜42%; conductive carbon black at a weight percentage of37%˜42%; a softening oil at a weight percentage of 14%˜17%; a processingaid at a weight percentage of 3%˜5%; and an accelerant at a weightpercentage of 1%˜2%. The electrode protuberances are integrally formedwith the main body, are distributed over a top portion of the main body,and correspond in positions to the acupoints in a human sole so thatwhen the human sole stamps on the top portion of the main body, the tipsof the electrode protuberances are pressed against the correspondingacupoints in the human sole. The socket is provided in the main body.One end of the socket is electrically connected to theelectrotherapeutic sole while the opposite end of the socket is formedwith an insertion hole. Once inserted into the insertion hole, anelectrotherapeutic pulse output terminal can send the electrotherapeuticpulses generated by an electrotherapeutic pulse generator sequentiallythrough the socket, the conductive carbon black in theelectrotherapeutic sole, and the tips of the electrode protuberances tothe corresponding acupoints in the human sole. Thus, a user only has tostamp on the electrotherapeutic sole, and an acupoint-stimulating effectsimilar to that achieved by acupuncture will be produced. Moreover, theelectrotherapeutic sole can conduct electric current effectively evenafter long-term use.

Another objective of the present invention is to provide a method formaking an electrotherapeutic sole, wherein the electrotherapeutic soleis configured as described above. The method begins by mixing NBR, at aweight percentage of 38%˜42%, thoroughly with conductive carbon black ata weight percentage of 37%˜42%, a softening oil at a weight percentageof 14%˜17%, a processing aid at a weight percentage of 3%˜5%, and anaccelerant at a weight percentage of 1%˜2% to form a sheet. The sheet isthen placed in the forming space of a forming mold and subjected tocompression molding at a forming temperature of 171˜189° C. for 199˜221seconds. Once the sheet cools down, the electrotherapeutic sole iscompleted. As the electrotherapeutic sole conducts electric currentthrough the conductive carbon black, there is no need to installadditional circuits, and this allows the conductive electrotherapeuticsole to be manufactured rapidly.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The objectives, technical features, and effects of the present inventioncan be better understood by referring to the following detaileddescription of some illustrative embodiments in conjunction with theaccompanying drawings, in which:

FIG. 1 is a top view of an electrotherapeutic sole according to thepresent invention;

FIG. 2 is a side view of the electrotherapeutic sole in FIG. 1;

FIG. 3 is the flowchart of the manufacturing process of the presentinvention; and

FIG. 4 schematically shows a forming mold for use in the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1 and FIG. 2, the present invention provides anelectrotherapeutic sole 1 and a method for making the same. Theelectrotherapeutic sole 1 can be used alone or placed in a piece offootwear (e.g., a slipper, sandal, aerobic shoe, or leather shoe) and isconfigured to be electrically connected to an electrotherapeutic pulsegenerator 2 (e.g., a TENS/EMS device). The electrotherapeutic sole 1 asshown in FIG. 1 and FIG. 2 is made of a mixture at least ofnitrile-butadiene rubber (NBR), conductive carbon black, a softeningoil, a processing aid, and an accelerant, wherein the NBR is at a weightpercentage of 38%˜42%; the conductive carbon black, 37%˜42%; thesoftening oil, 14%˜17%; the processing aid, 3%˜5%; and the accelerant,1%˜2%. In other embodiments of the present invention, additionalingredients may be included to modify the properties (e.g., elasticity,hardness, and/or electrical conductivity) of the electrotherapeutic sole1.

With continued reference to FIG. 1 and FIG. 2, the electrotherapeuticsole 1 includes a main body 11, a plurality of electrode protuberances13, and a socket 15. The main body 11 is a thin plate having a thicknessof about 1 mm The electrode protuberances 13 are integrally formed withthe main body 11 and are distributed over a top portion of the main body11 in a way that corresponds to the way in which acupoints aredistributed in a human sole. As most people's soles are not entirelyflat but are concavely curved on the inner side (where the arch is), theelectrode protuberances 13 in this embodiment vary in height, with thosecorresponding in position to the arch being the highest; consequently,the maximum thickness of the electrotherapeutic sole 1 reaches 4.5˜6.5mm (which is a combined height of the main body 11 and the electrodeprotuberances 13). The heights of the electrode protuberances 13 are sodesigned that when a user's sole stamps on the top portion of the mainbody 11, the tips of the electrode protuberances 13 are pressed againstthe corresponding acupoints in the user's sole.

As shown in FIG. 1 and FIG. 2, the socket 15 is provided in the mainbody 11 at a position corresponding to the arch of a human sole (i.e.,the area indicated by 1A in FIG. 1). The socket 15 has one endelectrically connected to the main body 11 and the opposite end formedwith an insertion hole 150. The insertion hole 150 corresponds inposition to a lateral edge of the main body 11 and is configured to beinserted by an electrotherapeutic pulse output terminal 21. Asconductive carbon black is a semiconductor and has relatively lowelectrical resistance, the electrotherapeutic sole 1 is renderedconductive when conductive carbon black is evenly distributed in theelectrotherapeutic sole 1. Once a user inserts the electrotherapeuticpulse output terminal 21 of the electrotherapeutic pulse generator 2(e.g., a TENS/EMS device) into the insertion hole 150, stamps on the topportion of the electrotherapeutic sole 1, and turns on theelectrotherapeutic pulse generator 2, the electrotherapeutic pulsesgenerated by the electrotherapeutic pulse generator 2 will passsequentially through the electrotherapeutic pulse output terminal 21,the socket 15, the conductive carbon black in the electrotherapeuticsole 1, and the tips of the electrode protuberances 13 to thecorresponding acupoints in the user's sole, thereby stimulating, ormassaging, the acupoints. It should be pointed out that while the socket15 in this embodiment is integrally formed with the main body 11 andcorresponds in position to the arch of the human sole, it is feasible inother embodiments of the present invention to design the socket 15 as aseparate unit to be placed at an arbitrary position in the main body 11,and the position of the insertion hole 150 may also be adjustedaccording to design requirements, provided that the socket 15 has oneend connected to the main body 11 and the opposite end formed with theinsertion hole 150 for electrical connection with the correspondingelectrotherapeutic pulse output terminal 21.

The method for making the electrotherapeutic sole 1 is detailed belowwith reference to FIGS. 1-3. First of all, the aforesaid materials(namely the NBR, the conductive carbon black, the softening oil, theprocessing aid, and the accelerant) are thoroughly mixed to form a sheet(step 301). The sheet in this embodiment has a hardness of 57˜63° A(Shore A) and a thickness of 4.5˜6.5 mm. After that, the sheet is placedin the forming space 40 of a forming mold 4 (step 302). As shown in FIG.4, the forming mold 4 includes an upper mold 4A and a lower mold 4B, andthe corresponding areas of the upper and lower molds 4A and 4B are eachconcavely provided with at least one sole-molding cavity 40A, 40B. Thesole-molding cavities 40A and 40B form the forming space 40 when theupper mold 4A and the lower mold 4B are put together. In addition, thesole-molding cavity 40A of the upper mold 4A is concavely provided witha plurality of sunken portions 401, and the sole-molding cavity 40B ofthe lower mold 4B has a flat bottom wall. In other embodiments of thepresent invention, however, the constituent parts of the forming mold 4may be modified and be different from those described above. Theconfiguration of the sole-molding cavity 40B in the lower mold 4B mayalso be modified according to production or design requirements. Forexample, in cases where the bottom side of the electrotherapeutic sole 1is required to be anti-slip, the sole-molding cavity 40B may have a wavyor other suitable configuration in order for the bottom side of theelectrotherapeutic sole 1 to have the corresponding configuration.

Referring again to FIGS. 1-4, the sheet is subjected to compressionmolding by the forming mold 4 at a forming temperature of 171˜189° C.for 199˜221 seconds, or until the sheet takes the shape of the formingspace 40 (step 303). After the compression molding process, thecompression-molded sheet is allowed to cool to complete theelectrotherapeutic sole 1 of the present invention (step 304). Theelectrotherapeutic sole 1 has a hardness of 57˜63° A (Shore A) and athickness of 4.5˜6.5 mm The electrode protuberances 13 are formed wherethe sheet corresponds to the sunken portions 401, and the bottom portionof the electrotherapeutic sole 1 has a flat surface due to theconfiguration of the sole-molding cavity 40B in the lower mold 4B.Besides, the socket 15 and the insertion hole 150 are automaticallyformed on the electrotherapeutic sole 1 thanks to the shape of theforming space 40 of the forming mold 4. Since different types ofelectrotherapeutic pulse output terminals 21 may vary in configuration(e.g., in length, it is feasible in other embodiments of the presentinvention to form the desired insertion hole 150, or more particularlyto adjust the shape and depth of the insertion hole 150, by drilling thecooled compression-molded sheet as appropriate, in order for thecorresponding electrotherapeutic pulse output terminal 21 to be securelyinserted into the insertion hole 150 and send the electrotherapeuticpulses generated by the electrotherapeutic pulse generator 2 (e.g., aTENS/EMS device) through the socket 15 to the conductive carbon black inthe electrotherapeutic sole 1 and then to the tip of each electrodeprotuberance 13. Now that the electrotherapeutic sole 1 depends on theconductive carbon black distributed therein, rather than additionalelectronic circuits conventionally required to be provided in theelectrotherapeutic sole, as pathways of current conduction, theelectrotherapeutic sole 1 is exempt from electronic component damageafter long-term use, which damage, however, is typical of theconventional electrotherapeutic soles; in other words, theelectrotherapeutic sole 1 of the present invention is expected to have alonger service life than its prior art counterparts.

While the invention herein disclosed has been described by means ofspecific embodiments, numerous modifications and variations could bemade thereto by those skilled in the art without departing from thescope of the invention set forth in the claims.

What is claimed is:
 1. A method for making an electrotherapeutic sole,wherein the electrotherapeutic sole comprises a main body, a pluralityof electrode protuberances, and a socket; the electrode protuberancesare integrally formed with the main body, protrude upward from a topportion of the main body, and correspond in position to acupoints in ahuman sole so that when the human sole stamps on the top portion of themain body, tips of the electrode protuberances are pressed againstcorresponding said acupoints in the human sole; the socket is providedin the main body; and the socket has an end electrically connected tothe main body and an opposite second end formed with an insertion hole;the method comprising the steps of: mixing at least nitrile-butadienerubber (NBR), conductive carbon black, a softening oil, a processingaid, and an accelerant thoroughly together to form a sheet, wherein theNBR is at a weight percentage of 38%˜42%; the conductive carbon black,37%˜42%; the softening oil, 14%˜17%; the processing aid, 3%˜5%; and theaccelerant, 1%˜2%; placing the sheet in a forming space of a formingmold; subjecting the sheet to compression molding by the forming mold ata forming temperature of 171˜189° C. for 199˜221 seconds; and allowingthe compression-molded sheet to cool, thereby completing theelectrotherapeutic sole such that an electrotherapeutic pulse outputterminal inserted into the insertion hole is able to sendelectrotherapeutic pulses generated by an electrotherapeutic pulsegenerator sequentially through the socket, the conductive carbon blackin the electrotherapeutic sole, and the tips of the electrodeprotuberances to the corresponding acupoints in the human sole.
 2. Themethod of claim 1, wherein the forming mold comprises an upper mold anda lower mold, the upper mold and the lower mold have corresponding areaseach concavely provided with at least a sole-molding cavity, thesole-molding cavities form the forming space, and the sole-moldingcavity of the upper mold is concavely provided with a plurality ofsunken portions in order for the sheet to form the electrodeprotuberances at positions corresponding respectively to the sunkenportions.
 3. The method of claim 2, further comprising the sub-step, tobe performed after the compression-molded sheet cools down, of drillingthe cooled compression-molded sheet to form the insertion hole.
 4. Themethod of claim 3, wherein the sheet formed by the mixing step has ahardness of 57˜63° A and a thickness of 4.5˜6.5 mm.
 5. The method ofclaim 4, wherein the sole-molding cavity of the lower mold is configuredto form a flat surface on a bottom portion of the electrotherapeuticsole.
 6. The method of claim 3, wherein the socket is provided in themain body at a position corresponding to the arch of the human sole, andthe sub-step of drilling comprises forming the insertion hole at alateral edge of the main body.
 7. The method of claim 4, wherein thesocket is provided in the main body at a position corresponding to thearch of the human sole, and the sub-step of drilling comprises formingthe insertion hole at a lateral edge of the main body.
 8. The method ofclaim 5, wherein the socket is provided in the main body at a positioncorresponding to the arch of the human sole, and the sub-step ofdrilling comprises forming the insertion hole at a lateral edge of themain body.